Collapsible dispensing tube

ABSTRACT

A collapsible dispensing container having a laminated tubular body, the laminated tubular body including a metal foil lamination, a layer of a polyolefin on the outside of the metal foil lamination, and, on the inside of the metal foil lamination and on the outside of the polyolefin layer, a layer of a copolymer resulting from the polymerization of 100 parts by weight of (a) at least 50 percent by weight of at least one nitrile having the structure ##STR1## wherein R is hydrogen, a lower alkyl group having from 1 to 4 carbon atoms, or a halogen, and (b) up to 50 percent by weight based on the combined weight of (a) and (b) of an ester having the structure ##STR2## wherein R 1  is hydrogen, an alkyl group having from 1 to 4 carbon atoms or a halogen, and R 2  is an alkyl group having from 1 to 6 carbon atoms, in the presence of from 1 to 40 parts by weight of (c) a copolymer of a conjugated diene monomer selected from the group consisting of butadiene and isoprene and an olefinically unsaturated nitrile having the structure ##STR3## wherein R has the foregoing designation containing from 50 to 95 percent by weight of polymerized conjugated diene and from 50 to 5 percent by weight of polymerized olefinically unsaturated nitrile.

BACKGROUND OF THE INVENTION

The present invention relates to collapsible dispensing tubes and, moreparticularly, to tubes formed from a laminated material.

Collapsible dispensing tubes made of both metallic and plastic materialsare well known. The metal tubes are generally impermeable to moistureand volatile oils and, therefore, are widely used for packagingpharmaceutical products, cosmetics, toiletries, and the like whichcontain these ingredients. They are also impervious to oxygen and hence,capable of protecting a container product against deterioration fromthis source.

However, the metal tubes such as are made from lead or aluminum arecostly to produce due to the high material cost and the manner in whichthe tubes must be made. This includes individual printing of each tubewith suitable decorative material after it has been formed Moreover, thechemical nature of the metals used often makes necessary the extra stepof completely coating the interior of the tube with a protective layerso as to preclude attack and corrosion of the metal by alkaline or acidcontents resulting in contamination of the contents by the reactionproducts.

On the other hand, plastic tubes are relatively inert and are bettersuited for many products that attack metal. Unfortunately, the thin bodywall of the plastics generally used is apt to be permeable, in varyingdegrees, to moisture, certain essential oils, perfumes, flavorings, andother volatile ingredients. Consequently, there is often a considerableloss of the volatile oils and moisture during storage, resulting in somedeterioration or dehydration or contained products such as toothpaste,shaving cream, medicinal ointments, etc. Too, many plastics favored forplastic tube manufacture are oxygen permeable and are inferior to metaltubes in this respect.

Even where permeability is not a factor, plastic tubes have a furtherserious disadvantage in that printing or decorative material applied tothe surface of the plastic will often not adhere readily, unless theplastic surface is first treated in some manner. This is an additionalexpense contributing to the cost of these tubes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a collapsible dispensing tube witha portion of the body broken away; and

FIG. 2 is an enlarged, partially sectional view of the laminated tubularbody.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a collapsible tube, generally designated by the numeral 10,having a tubular body 12 which has a longitudinally extending side seam(not shown). The side seam ordinarily is closed at one end after fillingby heat sealing or other techniques as shown at 14. The tubular body 12mounts at its opposite end a plastic headpiece 16 which is usuallyshaped to provide a threaded neck so that a cap 18 may be securedthereto when the tube 10 is filled with product 20. Headpiece 16 ispreferably made from a material which can be fused by heat and/orpressure to lamina 23, or welded to lamina 23 by sonic welding,induction welding, or the like. However, other headpiece configurationsmay be employed without departing from the scope of the invention.

The tubular body 12, as shown in FIG. 2, comprises a plurality of layerslaminated or otherwise bonded one to the other. The body 12 comprises anintermediate foil layer 22 which provides the barrier protection againstoxygen absorption from the atmosphere and essential oil permeationoutwardly through the tube body 12. The thickness of this metallic foilis sufficient to impart the requisite barrier properties and yet ismaintained relatively thin in the interest of cost and pliability of thecontainer during use. Aluminum foil has been found particularly suitablefor this use, although other metallic foil such as sheet steel or tinplate may also be utilized.

On the inside of foil layer 22 is a layer 23. Layer 23 is a flexible,thermoplastic polymer having a low permeability to fluids. Thethermoplastic polymers having high barrier properties which may be usedas layer 23 include the materials disclosed in U.S. Pat. No. 3,426,102issued Feb. 4, 1969. The disclosures of this patent are hereinincorporated and made part of this disclosure. The fluid barriermaterials disclosed in this patent are those resulting from thepolymerization of 100 parts by weight of (a) at least 50 percent byweight of at least one nitrile having the structure ##STR4## wherein Ris hydrogen, a lower alkyl group having from 1 to 4 carbon atoms, or ahalogen, and (b) up to 50 percent by weight based on the combined weightof (a) and (b) of an ester having the structure ##STR5## wherein R₁ ishydrogen, an alkyl group having from 1 to 4 carbon atoms or a halogen,and R₂ is an alkyl group having from 1 to 6 carbon atoms, in thepresence of from 1 to 40 parts by weight of (c) a polymer of aconjugated diene monomer selected from the group consisting of butadieneand isoprene and an olefinically unsaturated nitrile having thestructure ##STR6## wherein R has the foregoing designation containingfrom 50 to 95 percent by weight of polymerized conjugated diene and from50 to 5 percent by weight of polymerized olefinically unsaturatednitrile.

Another preferred barrier material also disclosed in U.S. Pat. No.3,426,102 is that prepared from the polymerization in aqueous medium of100 parts by weight of a mixture of (a) from about 70 to 95 percent byweight of acrylonitrile and (b) from about 30 to about 5 percent byweight of methyl acrylate in the presence of from about 1 to about 20parts by weight of (c) a copolymer of butadiene and acrylonitrile, saidcopolymer containing from about 60 to about 80 percent by weight ofpolymerized butadiene and from about 40 to about 20 percent by weight ofpolymerized acrylonitrile.

As previously stated, the olefinic nitrile in the composition ispreferably acrylonitrile or methacrylonitrile or analogous polymersprepared from the higher nitriles and the diene-nitrile rubber comprisesbutadiene and acrylonitrile. As the relative amount of rubbery copolymerof butadiene and acrylonitrile is increased in the final polymericproduct, the impact strength of the fluid barrier lamina increases andthe gas and vapor barrier properties decrease somewhat. It is generallyadvantageous to use just enough of the rubber copolymer to impart thedesired impact strength to the polymeric product and to retain theoptimum gas and vapor barrier properties in the product. A suitablecommercially available composition for making plastic bottles of thepresent invention, which are suitable for carbonated beverages and otheruses, is that sold by the Standard Oil Company of Ohio under thetrademark Barex 210, although other compositions are also satisfactory.

In each of the fluid barrier materials disclosed in U.S. Pat. No.3,426,102, the ester (b) may be replaced by an ester having thestructure ##STR7## wherein R₈ has the foregoing designation. Examples ofsuch esters are vinyl acetate, vinyl formate, vinyl propionate, vinylbutyrate, vinyl decanoate, vinyl benzoate, and the like.

Also, in each of the fluid barrier materials disclosed in U.S. Pat. No.3,426,102, from about 5 to about 50 weight percent of the nitrilemonomer may be replaced with a dicyanobutene monomer, such as1,3-dicyano-1-butene, 1,4-dicyano-1-butene, or 2,4-dicyano-1-butene, ora mixture of two or more of these isomers. The mixture can be graftedonto an elastomeric substrate in the same manner disclosed for graftingthe nitrile monomer in U.S. Pat. No. 3,426,102.

On the outside of foil layer 22 is preferably a polyolefin, generallytaking the form of a low density polyethylene. However, other materialssuch as polypropylene, polybutylene, and the like may be used.

On the outside of the tubular body is layer 25 which is bonded to layer24. Layer 25 is a material identical in composition to layer 23. Outerlayer 25 is substantially transparent and forms the exterior surface ofthe tube. Layer 25 serves to protect the tube body 12 from abuse duringhandling and also to effectively seal the laminated collapsible tube 10from absorbing any liquids that may come in contact with its exteriorsurface. It is thus readily apparent that any decoration or indicia (notshown) that may be placed on the surface of layer 24 will be protectedand be visible through the clear layer 25. Of course, indicia could beprinted directly on lamina 25. This decoration is preferably printed onlayer 24 before the laminate material is formed into the tubular body10, thus permitting greater versitility and economy than is ordinary inpreformed tube bodies.

Layer 23 prevents the foil layer 22 from chemically reacting with thecontents of the tube. Furthermore, layer 23 will not absorb the variousoils or other chemicals contained in product 20.

In another embodiment of the invention (not shown) the outer layer 25may be deleted.

The various lamina may be joined by any conventional techniques.Exemplary of these techniques is gluing, co-extruding, and the like.

We claim:
 1. A collapsible dispensing container having a laminatedtubular body, said laminated tubular body including a metal foillamination, a layer of a polyolefin on the outside of said metal foillamination, and, on the inside of said metal foil lamination and on theoutside of said polyolefin layer, a layer of a copolymer resulting fromthe polymerization of 100 parts by weight of (a) at least 50 percent byweight of at least one nitrile having the structure ##STR8## wherein Ris hydrogen, a lower alkyl group having from 1 to 4 carbon atoms, or ahalogen, and (b) up to 50 percent by weight based on the combined weightof (a) and (b) of an ester having the structure ##STR9## wherein R₁ ishydrogen, an alkyl group having from 1 to 4 carbon atoms or a halogen,and R₂ is an alkyl group having from 1 to 6 carbon atoms, in thepresence of from 1 to 40 parts by weight of (c) a copolymer of aconjugated diene monomer selected from the group consisting of butadieneand isoprene and an olefinically unsaturated nitrile having thestructure ##STR10## wherein R has the foregoing designation containingfrom 50 to 95 percent by weight of polymerized conjugated diene and from50 to 5 percent by weight of polymerized olefinically unsaturatednitrile.
 2. The composition of claim 1 wherein the (a) component ismethacrylonitrile.
 3. The composition of claim 2 wherein there isemployed 100 percent by weight of (a).
 4. The composition of claim 1wherein the (a) component is acrylonitrile.
 5. The composition of claim4 wherein the (b) component is ethyl acrylate.
 6. The composition ofclaim 4 wherein the (b) component is methyl acrylate.
 7. The compositionof claim 6 wherein there is employed a mixture of 75 percent by weightof (a) and 25 percent by weight of (b).
 8. A collapsible dispensingcontainer having a laminated tubular body, said laminated tubular bodyincluding a fluid impervious metal foil lamination, a layer of apolyolefin on the outside of said metal foil lamination, and, on theinside of said metal foil lamination and on the outside of saidpolyolefin layer, a layer of a copolymer resulting from thepolymerization of 100 parts by weight of a mixture of(a) from 70 to 95percent by weight of acrylonitrile, and (b) from 30 to 5 percent byweight of methyl acrylate in the presence of from 1 to 20 parts byweight of (c) a copolymer of butadiene and acrylonitrile said copolymercontaining from 60 to 80 percent by weight of polymerized butadiene andfrom 40 to 20 percent by weight of polymerized acrylonitrile.